This invention relates to a coil spring manufacturing machine which is controlled by a digital computer.
Old type coil spring manufacturing machines were constructed by machinery elements. Although, through progress of the electric industry, an invention has been created which detects the number of windings to utilize the detection output for controlling a coil spring sequence circuit of the manufacturing machine.
Japanese patent application No. 42-65018 discloses an invention which provides cam switches and counters which control a magnetic clutch and brake and provides a plurality of motors for effecting the feeding of wire, rotating a mandrel to introduce a pitch to the coil spring and also introducing a back ring to the fully wound coil spring is carried out by operation from the motors. It is possible to form many types of coil springs, but in the course of preparation for starting an actual job for manufacturing coil springs, it is very complicated to change the operating position and to specify the operating position of the cam switch for adjusting same for formation of the coil spring which is proposed for manufacture. In addition, conventional coil spring machines are obliged to be enlarged in size due to same being provided with a plurality of motors. In recent years, through progress of the electronic industry, commercially supplied micro-computers which may control all the actions and operations of coil spring manufacturing machines in accordance with a program stored in a memory for formation into the desired forms of coil springs have been used. However, a coil spring manufacturing machine simplified in it's mechanical construction, utilizing a single drive motor and having a function for forming many types of coil springs has not been designed.